Marking the seasons

This article discusses the seasons, so it covers the entire year.

We mark the changes in season with our wardrobes, our moods and our calendars, but at a deeper level, the seasons are delineated by the position of the Sun in four constellations. In ancient times, they were Aries, where the start of Spring was marked by the First Point in Aries; Cancer, where the sun was over the Tropic of Cancer on the first day of Summer; Libra, marking the first day of Autumn; and Capricornus, where the sun was over the Tropic of Capricorn on the first day of Winter. Because of the often-mentioned precession of Earth’s axis, those points drift westward along the ecliptic, and are now in Pisces, Gemini, Virgo and Sagittarius. Here’s a table to summarize.

Season CurrentAncient
Spring PiscesAries
Ecliptic (i.e. Sun) crosses Equator, going north First Point in Aries
Summer GeminiCancer
Ecliptic farthest north of Equator Tropic of Cancer
Autumn VirgoLibra
Ecliptic crosses Equator, going south (Sorry – no “last point in Libra”)
Winter SagittariusCapricornus
Ecliptic farthest south of Equator Tropic of Capricorn

These maps show two of these constellations – a pair of dim old goats! Aries is the Ram and Capricornus is the Goat. Both are faint and fairly small, and would be largely unknown if not on the “Zodiac”. On the other hand, when you do see something bright in this region, it will be a planet. Aries culmulates in October; Capricornus in late August.

There are few interesting sights in these constellations – in fact there is only one Messier object in Capricornus and none in Aries. The tail of the Goat has some interesting double stars, too. But that’s about it – just a couple of dim, even dull, old goats.

Capricornus & Sagittarius (Teapot)
Sky School